Mayor Bloomberg’s Republican mayoral challenger, Thomas Ognibene, is calling on Manhattan’s district attorney to open an investigation into potential “illegal campaign activity” by the Bloomberg campaign.

Mr. Ognibene said he is concerned about the status of John Haggerty Jr., a member of the Bloomberg campaign staff who has been at the center of a heated political fight over the Republican-primary petition-gathering process in Queens. A Republican mayoral candidate must collect 7,500 signatures citywide to be included on the primary ballot; Mr. Ognibene said he has obtained about 7,900.

Mr. Haggerty’s opponents in Queens have alleged that the Forest Hills resident joined the Bloomberg campaign at a six-figure salary to advance his personal political ambitions and to keep Mr. Ognibene off the ballot for the September 13 GOP primary.

The Bloomberg campaign confirms that Mr. Haggerty is a paid member of its staff. However, in the latest campaign-finance report submitted by the mayor, which was filed last week, there is no mention of any payment to Mr.Haggerty.

In a May 26 story in The New York Sun, a spokesman for the Bloomberg campaign, Stuart Loeser, said he would not comment on Mr. Haggerty’s role in the campaign and declined to divulge Mr. Haggerty’s pay, which he said would be disclosed in last week’s filing.

When asked why payments to Mr. Haggerty had not in fact been disclosed, Mr. Loeser yesterday said: “He hasn’t submitted a bill.”

“His salary will be disclosed,” Mr. Loeser added.

Mr. Haggerty, he said, joined the Bloomberg staff in “mid- to late May,” shortly after the May 16 campaign finance-filing deadline. In March, the Albany Times Union reported that Mr. Haggerty was resigning his $99,425-a-year job heading Governor Pataki’s legislative affairs office to take up a post as Mr. Bloomberg’s deputy campaign manager.

“I’d like to know how he lived all this time,” Mr. Ognibene said. “I didn’t see him once on a street corner in Queens with a tin cup.”

An Albany-based election lawyer familiar with Republican politics in the city and state, Thomas Marcelle, said: “If the Bloomberg campaign is paying him and didn’t disclose it, it’s a clear violation of the law.” Mr. Haggerty, he added, “is obviously getting paid by someone; the question is by whom. You have to disclose that.”

Mr. Ognibene said that if Mr. Haggerty was not paid during the last campaign-finance filing period, his services should be disclosed as an in-kind contribution to the Bloomberg campaign. Because the mayor’s campaign-contribution filing listed no outside donations, Mr. Ognibene said the mayor “may be the beneficiary of illegal campaign contributions.” He is calling for an investigation into the matter.

Mr. Marcelle, however, said that if indeed Mr. Haggerty had simply not been billed for his services, he must still be listed in the campaign’s filings under “liabilities,” a category separate from “expenditures.”

“He should be listed as a debt the campaign incurred. They know what they’re paying him. Just because they haven’t received the bill doesn’t mean they don’t know what that liability is,” Mr. Marcelle said. “That’s part of their mandatory disclosure.”

A search of the New York City Campaign Finance Board’s database for Bloomberg-campaign liabilities yielded “zero” results. Mr. Ognibene said the Bloomberg campaign’s decision not to list Mr. Haggerty in its campaign-finance reporting was probably motivated by a desire to distance itself from efforts to block a Republican primary.

Mr. Ognibene has alleged that Mr. Haggerty, working on behalf of the Bloomberg campaign, is behind challenges to Mr. Ognibene’s petition signatures, which, if successful, could keep him off the ballot in September.

On Monday, a campaign strategist for the mayor, William Cunningham, was quoted in the New York Times as saying it was merely a “happy coincidence” that Mr. Haggerty was listed as the contact person on a challenge to Mr. Ognibene’s petitions filed by his brother, Bart Haggerty, also a Queens Republican activist.

In fact, a copy of Bart Haggerty’s challenge shows that he, and not his brother, is listed as the contact person. But on four of the six challenges filed to Mr. Ognibene’s petitions – by Mireya Giraldo, of Brooklyn; Daniel Hennessy, of Staten Island; Karen Chen, of Brooklyn, and Jayson Lefer, of Brooklyn – John Haggerty is listed as the “objector’s contact person.”

On all four petitions, the contact information provided for Mr. Haggerty lists his Forest Hills address, a mobile telephone number – and a fax number that a Bloomberg staffer confirmed was for Bloomberg-campaign headquarters.

The portrayal of the Haggerty connection to the challenges as a “coincidence” by the Bloomberg campaign infuriated Mr. Ognibene. “Having the mayor lie to the public about challenges to my petitions is more offensive than the challenges themselves,” he said.